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Sentence Counter

Free online sentence counter. Count sentences, average words per sentence, and readability level — live as you type. No signup required.

0Sentences
—Avg words / sentence
—Avg chars / sentence
—Readability

How to use the Sentence Counter

  1. Paste or type your text into the box. Counts update live.
  2. Check the stats row — sentence count, average words per sentence, average characters per sentence, and readability level.
  3. Review highlights — the tool shows your longest and shortest sentences so you can identify what to trim or expand.
  4. Browse the sentence list — each sentence is numbered with its word count, making it easy to spot outliers.

Recommended sentence length by context

Web content / blogs

14–18 words

Short sentences improve scannability and mobile readability

Business writing

15–20 words

Clear and professional; avoid exceeding 25 words

Academic / technical

20–25 words

Longer sentences acceptable when precision requires it

Legal / contracts

25–40 words

Dense by convention; plain-language reforms push for shorter

Children's content

6–10 words

Simple vocabulary + short sentences = accessibility

Social media posts

8–12 words

Punchy, scannable — hooks matter more than completeness

How readability is scored

This tool estimates readability from average sentence length — a simplified but effective proxy for reading difficulty. Shorter sentences are generally easier to parse because they require less working memory to hold in mind while reading.

Easy ≤ 12 words/sentence

General public, social media, landing pages

Moderate 13–17 words

Business emails, blog posts, journalism

Complex 18–25 words

Academic papers, technical documentation

Very Complex > 25 words

Legal text, dense academic prose

Frequently Asked Questions

How does the sentence counter detect sentences?

The tool splits text on sentence-ending punctuation (period, exclamation mark, question mark, ellipsis) followed by a space and an uppercase letter. Common abbreviations like Mr., Dr., and Mrs. are protected so they don't cause false splits.

What is average words per sentence?

Average words per sentence is the total word count divided by the sentence count. It is one of the simplest readability metrics. Most style guides recommend keeping sentences under 20 words for professional writing and under 15 words for web content.

What do the readability levels mean?

Readability is estimated from average sentence length: Easy (≤12 words/sentence) is suitable for general audiences; Moderate (13–17) suits business writing; Complex (18–25) is academic or legal; Very Complex (>25) is dense technical or legal text.

Why does my sentence count differ from Word's count?

Different tools use different algorithms for sentence detection. Microsoft Word uses a more sophisticated parser that accounts for dialogue, lists, and special cases. Simple text like headings or bullet points may count differently.

How many sentences should a paragraph have?

For web content, aim for 3–5 sentences per paragraph. Academic writing typically uses 5–8. Very short paragraphs (1–2 sentences) are fine for emphasis or online scanning. Avoid paragraphs longer than 8 sentences — readers lose track.

Does the tool handle questions and exclamations?

Yes. The counter treats periods, exclamation marks, and question marks as sentence endings. Multiple punctuation marks like "!?" count as a single sentence boundary.

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